1) Field of the Invention
This invention relates to inhibitors of neutrophil functions (hereinafter called xe2x80x9cneutrophil function inhibitorsxe2x80x9d), each of which comprises a glucosamine salt as an active ingredient. These neutrophil function inhibitors are useful as drugs, drinks, foods or the like for the prevention or treatment of troubles caused by exaltation of neutrophil functions, for example, respiratory disease syndrome (RDS), adult respiratory disease syndrome (ARDS) and other neutrophil-associated inflammations.
2) Description of the Related Art
A neutrophil is principal one of granules in a leukocyte. When an exogenous substance such as bacteria invades a living body, neutrophils emigrate to the invaded site, ingest the exogenous substance, have active oxygen generated and at the same time, antibiotic proteins (granules) such as lysozyme and defensins released, and play an important role to expel the exogenous substance under the action of the antibiotic proteins and also under the action of various acid hydrolases. However, an excessive extracellular release of these active oxygen and antibiotic proteins causes destruction of a tissue, and in some instances, further aggravates an acute inflammation occurred by the invasion of the exogenous substance. In the case of certain specific diseases such as respiratory distress syndrome, adult respiratory distress syndrome and other neutrophil-associated inflammations, this action of neutrophils is known to give adverse effects on these diseases.
Glucosamine salts, especially the sulfate or the hydrochloride have been produced, for example, by the process disclosed in JP1-28757 B or U.S. Pat. No. 3,683,076. U.S. Pat. No. 3,683,076 also discloses that glucosamine salts in the form of capsules or tablets are used as arthritis remedies and the like. However, absolutely nothing is known about effects of glucosamine salts on leukocytes.
Upon invasion of an exogenous substance into a living body, neutrophils play an important role to protect the living body from the exogenous substance. As has been described above, however, functions of neutrophils may give negative effects on the living body in some instances. An object of the present invention is to provide a drug or composition for preventing or lessening a trouble which may occur by such negative effects.
The present inventors have proceeded with a variety of research on effects of glucosamine salts which are hydrolyzates of chitosan and are substantially free of toxicity. As a result, it has been unexpectedly found that glucosamine salts have effects to inhibit functions of a neutrophil, one of the principal components of a leukocyte, for example, emigrating ability, ingesting action on exogenous substances, granule releasing ability, active oxygen releasing ability and the like, leading to the completion of the present invention.
In one aspect of the present invention, there is thus provided a neutrophil function inhibitor comprising a glucosamine salt as an active ingredient.
In another aspect of the present invention, there is also provided a preventive or remedy for a disease caused as a result of an excessive extracellular release of active oxygen and antibiotic proteins by neutrophils, comprising a glucosamine salt as an active ingredient.
In a further aspect of the present invention, there is also provided a dietetic drink or food for a disease caused as a result of an excessive extracellular release of active oxygen and antibiotic proteins by neutrophils, comprising a glucosamine salt as an active ingredient.
Specifically, the disease may be respiratory disease syndrome or adult respiratory disease syndrome.
In a still further aspect of the present invention, there is also provided a method for the prevention or treatment of respiratory disease syndrome or adult respiratory disease syndrome, which comprises administering an effective amount of a glucosamine salt to a human being.
In a still further aspect of the present invention, there is also provided use of a glucosamine salt for the prevention or treatment of respiratory disease syndrome or adult respiratory disease syndrome.
Specifically, the glucosamine salt may be selected from the group consisting of glucosamine sulfate, glucosamine hydrochloride, glucosamine acetate, glucosamine citrate and glucosamine malate.
Glucosamine salts can significantly inhibit the emigrating ability and ingesting action of neutrophils, the release of granules from neutrophils, and the release of active oxygen by neutrophils. Therefore, these glucosamine salts are useful as neutrophil function inhibitors, and can be employed as drugs, drinks, foods or the like for the prevention and/or treatment of troubles caused by exaltation of neutrophil functions, for example, respiratory disease syndrome, adult respiratory disease syndrome and other neutrophil-associated inflammations.